Transcarotid Artery Endovascular Reconstruction of the Aortic Arch by Modified Bifurcated Stent Graft for Stanford Type A Dissection

Protocol for Guo's aortIc Arch recoNstrucTion: a prospective, multicentre and single-arm study to evaluate the safety and efficacy of the WeFlow-Arch modular inner branch stent-graft system for aortic arch lesions (GIANT study)

INTRODUCTION

Endovascular repair of the entire aortic arch provides treatment opportunities for patients with aortic arch lesions who are intolerant to open surgery. However, the complex anatomical configuration, high-speed blood flow and long access from the femoral artery increase the difficulty of endovascular aortic arch repair. On the basis of our earlier studies, a new modular inner branch stent-graft system was developed specifically for lesions located in the aortic arch and part of the ascending aorta. This study aims to evaluate the safety and efficacy of the novel modular branch stent-graft system in patients with aortic arch lesions who are unsuitable for open aortic arch replacement.

METHODS AND ANALYSIS

This prospective, multicentre, single-arm, clinical trial will enrol 80 patients with aortic arch lesions requiring intervention, namely, true aortic arch aneurysms, pseudo-aortic arch aneurysms and penetrating ulcers involving the aortic arch. Clinical information and CT angiography (CTA) images will be collected and analysed to investigate the safety and efficacy of the novel modular branch stent-graft system. Patients will be followed up for 5 years. The primary outcome will be all-cause mortality and severe stroke within 12 months after the procedure. In addition, this trial will evaluate mid-term to long-term clinical and imaging outcomes through the annual clinical and CTA follow-up for 2-5 years postoperatively.

ETHICS AND DISSEMINATION

We have registered the study on a registry website (https://clinicaltrials.gov/ct2/home). The study findings will be disseminated through peer-reviewed journals, physician newsletters, conferences and the mass media.

TRIAL REGISTRATION NUMBER

NCT04765592.

Alternative management of proximal aortic dissection: concept and application

Open surgery remains the mainstay of treatment for acute type A aortic dissection and should be offered to most patients. However, there are elderly patients in which surgical treatment may be deemed extremely high risk or futile. Endovascular treatment approaches have been applied to a small number of these patients and data are limited to case reports and small series. The application of endovascular therapies to ascending aorta is currently limited by anatomical and technical challenges posed by the dynamic motion of the ascending aorta and the proximity of vital structures to intended landing zones (aortic valve, coronary arteries, and supra-aortic branches) and lack of specially designed endografts to address these issues. While thoracic endovascular aortic repair (TEVAR) has replaced open aortic repair for a suitable lesion in distal aortic dissection, some selected patients with type A aortic dissection at high surgical may be candidates. Hence, there is potential because, in proximal (Stanford type A) dissections, 10–30% of patients are not accepted for surgery, and 30–50% are technically amenable for TEVAR. Recent experience has shown that carefully selected patients with favorable anatomical characteristics may be subject to endovascular stent-graft treatment as a last resort with mixed results. Technical improvement is necessary to offer. satisfactory endovascular options in non-surgical candidates.

The future of stenting in patients with type A aortic dissection: a systematic review

Acute type A aortic dissection (ATAAD) carries high morbidity and mortality rates and is a clinical emergency. The reported mortality rate is 50% to 65% within the first 48 hours without surgical intervention. Open surgery therefore remains the gold standard management for ATAAD. However, in patients who are deemed unfit for surgery and where possible, endovascular repair offers a useful alternative to medical treatment alone or high-risk open surgical repair. Several case reports, case series, and retrospective studies have reported good outcomes following endovascular treatment. The endovascular option also has comparable early and late outcomes, favourable aortic remodelling, and satisfactory overall survival despite having a higher-risk patient cohort. However, stenting in patients with ATAAD undoubtedly still has several limitations and technical challenges.

Carotid Access for Aortic Interventions: Genius or Madness?

The endovascular-first approach remains is omnipresent ubiquitous amongst in the vascular community today. However, several key issues have ensued remain, one of which involves the choice of vessel site. Although the transfemoral route is the first-line approach has been established as first-line approach in endovascular interventions of the aorta (endovascular aortic repair [EVAR], thoracic endovascular aortic repair [TEVAR], and transcatheter aortic valve implantation [TAVI]), there remains a select some group of patients who are contraindicated for the aforementioned this as well as for alternatives vessel routes such as the transapical approach. The carotid artery, first used in aortic aneurysm repair, is potential alternative for these patients. Emerging evidence appears to support this relatively unpopular approach in EVAR, TEVAR and TAVI. Sporadic case reports and series have reported the transcarotid approach for EVAR and TEVAR, and collectively show relatively low rates of mortality and neurological complications. For TAVI, the carotid artery appears to be a safe and effective route of access compared to the transapical and even the transfemoral approach. However, technical aspects have not been ironed out; there are procedural variations, for example, in type of anaesthesia used, intraoperative neurological monitoring and choice of common carotid artery. The overall quality of evidence is poor, since the majority of it consists of case reports, and retrospective and prospective cohort studies. Although a randomised controlled trial (RCT) is needed to compare the transcarotid against the transfemoral approach, this is unlikely to take place because of ethical considerations. Therefore, the authors recommend future research to consider cohort studies with adequately powered sample sizes to establish any firm conclusions. However, as transcarotid procedures are performed infrequently, most institutions will have relatively small sample sizes. Therefore, it is recommended that collaborative efforts are undertaken to increase the overall sample size in the cohort analysis.

Carotid Access for Endovascular Repair of Aortic Pathology: A Systematic Review

BACKGROUND

Endovascular repair is now preferred to open access for the management of aortic diseases. This is typically performed via the femoral artery; however, not all patients are eligible for this. This systematic review summarizes the current evidence for utilizing the carotid artery as an alternative access route.

METHODS

A systematic review was conducted as per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines using 4 electronic databases.

RESULTS

The search found 11 case reports representing 12 patients eligible for analysis (mean age 64.5 years). This included 3 thoracic aneurysms, 3 abdominal aneurysms, 4 penetrating ulcers, 1 endoleak, and 1 pseudoaneurysm. An open procedure was contraindicated in 83% (10/12) due to the poor physiological fitness of the patient. In 75% (9/12) of cases, traditional endovascular access was contraindicated by severe iliac disease. The remainder were contraindicated because of an existing ligated aortic stump (1/12, 8.3%) or technical difficulty with graft deployment via the femoral artery (2/12, 16.7%). There was 1 death, with the 30-day mortality 8.3%. The same patient suffered the only spinal ischemia before death (8.3%). There were no cases of stroke (0%), with one case of transient ischemic attack (8.3%).

CONCLUSIONS

Although there is a relative paucity of literature, this study demonstrates when traditional endovascular access is impossible and an open procedure contraindicated, carotid artery access for endovascular repair of aortic pathology is a viable alternative with good 30-day survival and low rates of neurological sequelae.

Complications and Perioperative Management of Patients Undergoing Thoracic Endovascular Aortic Repair

Endovascular treatments have become increasingly common for patients with a variety of thoracic aortic pathologies. Although considered less invasive than traditional open surgical approaches, they are nonetheless complex procedures. Patients undergo manipulation of an often calcified aorta near the origin of the carotid and subclavian vessels and have stents placed in a curved vessel adjacent to a perpetually beating heart. These stents can obstruct blood flow to the spinal cord, induce an inflammatory response, and in rare cases erode into the adjacent trachea or esophagus. Renal complications range from contrast-induced nephropathy to hypotension and ischemia to dissection. Emboli can lead to strokes and mesenteric ischemia. These patients have complex medical histories, and skilled perioperative management is critical to achieving the best clinical outcomes. Here, we review the medical management of the most common complications in these patients including stroke, spinal cord ischemia, renal injury, retrograde dissections, aortoesophageal and aortobronchial fistulas, postimplantation syndrome, mesenteric ischemia, and endograft failure.

Endovascular Repair of Type A Aortic Dissection: Current Experience and Technical Considerations

Dissection of the ascending aorta, type A aortic dissection (TAAD), represents a surgical emergency with high morbidity and mortality. Current open surgical techniques, although state-of-the-art procedures and having improved outcomes for patients with TAAD over the last decades, confer significant risk of complications and death. Recently, endovascular techniques for repair of both the abdominal and thoracic aorta have gained acceptance within the vascular and cardiovascular surgical communities as a useful tool in select pathologies and patient populations. As development of endovascular technology proceeds ever closer to the aortic valve, thoracic endovascular repair for TAAD deserves special investigation. A comprehensive literature search for studies reporting outcomes of endovascular repair in the ascending aorta was performed. In this review, we compile the worldwide experience of thoracic endovascular repair for TAAD as well as imaging studies for patient selection and the use of hybrid (open plus endovascular) techniques. The authors discuss the remaining challenges that preclude its broader adoption in this role, namely patient selection and device specificity.

Trans-Carotid Placement of Balloon Expandable Covered Stent for Unplanned Left Carotid Coverage during Endovascular Repair of Distal Arch Aneurysm

We present a technique for endovascular management of unplanned coverage of the left common carotid artery during endovascular repair of a distal aortic arch aneurysm. A balloon expandable covered stent was placed into the proximal left common carotid artery by neck incision.

Endovascular repair of the aortic arch in pigs by improved double-branched stent grafts

INTRODUCTION

This study aimed to evaluate the feasibility of total endovascular repair of the aortic arch in pigs using improved integrated double-branched stent grafts.

METHODS

Improved self-expandable stent grafts with a main body and two integrated branches were prepared for the repair of the aortic arch in six pigs. The feasibility of using these stent grafts was evaluated with arteriography, computed tomography (CT), computed tomography angiography (CTA) and autopsy three months following the procedure.

RESULTS

The double-branched stent grafts were placed successfully in the aortic arch in all six pigs. All pigs survived for at least three months and their biological behaviour was normal. Arteriography, CTA and animal necropsy revealed good fixation in all cases. Aortic valve function and coronary ostia remained intact, and CT of the head did not detect any lesion of cerebral infarction.

CONCLUSIONS

Endovascular repair of the aortic arch with an integrated double-branched stent graft is safe and feasible in animal studies.

Endovascular repair of the half aortic arch in pigs with an improved, single-branched stent graft system for the brachiocephalic trunk

The objective of this study was to evaluate the feasibility of endovascular repair of half of the aortic arch in pigs using an improved, integrated, single-branched stent graft for the ascending aorta and brachiocephalic trunk (BCT). We designed an improved stent graft in an integrated fashion and deployed the stent grafts into the ascending aortas and BCT of eight pigs. The feasibility of the stent graft deployments was evaluated three months after the procedures using arteriography, computed tomography angiography (CTA) and animal autopsy. The stent grafts were successfully deployed in eight pigs. All animals survived for at least three months. Arteriography, CTA and animal necropsy revealed good stent fixation in eight cases. Their head CT scans found no evidence of cerebral infarction. In conclusion, endovascular repair of the half aortic arch with the integrated single-branched stent graft system appears to be safe and feasible in pigs.